Europe's beleaguered ExoMars rover is unlikely to launch before 2026 as the European Space Agency ponders a path forward for the mission, including finding a new rocket, replacing Russian-built parts in cooperation with NASA, or restarting its partnership with Russia in case that country's war in Ukraine ends soon.
ESA representatives outlined their plans for the mission in a press conference on Thursday (March 17) after officially suspending cooperation with Russia's space agency Roscosmos as a result of sanctions imposed on Russia by ESA member states.
"We have to do detailed studies of what this means and how the rover can arrive on the Mars surface," ESA director general Josef Aschbacher said in the briefing. "We have to see what the options are in terms of Europe alone or with partners."
He added that ESA "was closely working with NASA to identify where NASA could help."
The space agency, however, did not rule out a possible future restart of the cooperation with Russia in case the war in Ukraine ends, an option that would come with the lowest additional price tag for the mission that has already cost ESA member states over $1.1 billion.
"The possibility of restarting that cooperation at some future date is available and would be compatible with the launch in 2024," David Parker, ESA director of human and robotic exploration, said in the same press conference. "More radical reconfigurations of the mission would lead to launches in 2026 or 2028."
The ExoMars rover, named Rosalind Franklin after the British chemist whose work led to the discovery of the DNA, was designed to search for traces of past and present life underneath the surface of Mars. The rover, equipped with a 6.6-foot-long (2 meters) drill, is, according to astrobiologists, more likely to find organic molecules on the Red Planet than NASA's Perseverance rover, which cannot reach too deep below the planet's scorched surface.
The ExoMars program consists of the Trace Gas Orbiter (TGO), which has been circling Mars since 2016, and the Rosalind Franklin rover. It was originally conceived in cooperation with NASA, but the American space agency withdrew from the mission in 2012 following budget cuts by the administration of President Barack Obama. The mission was only saved from cancellation when Russia stepped in to plug the hole in funding.
Roscosmos was not only expected to launch the rover on its Proton rocket, but also oversee the construction of the rover's landing platform. Parker said in the press conference there were additional Russia-made technologies on the rover.
"There are scientific instruments and there are also the radioisotope heating units that are used to keep the rover warm at night once it's on the surface of Mars," Parker said. "So we need to investigate alternatives for that technology in case we reconfigure the mission. As far as the landing system technologies go, some of those are already available in Europe, and many of them were demonstrated actually in 2016 with the Schiaparelli lander."
Schiaparelli was an experimental landing platform that traveled to Mars together with the TGO as part of the first leg of the ExoMars mission. The platform, however, crashed on the planet's surface due to a software glitch. The launch of Rosalind Franklin, originally scheduled for 2018, was delayed first to 2020 because of problems with landing parachutes, and, eventually to 2022, partially as a result of the COVID-19 pandemic.
Parker said the rover can wait for several years in a clean room, but at some extra cost. The delay, he added, will not diminish its scientific potential.
"Nobody else has built an analytical life search machine capable of searching at the molecular level for the possibility of past life on Mars," Parker said. "We're very proud of what has been achieved by the team so far. And I guess Mars is four and a half billion years old. So we just have to wait a few more years for it to reveal all of its secrets."
Aschbacher said in the news conference that the space agency will evaluate its other involvements with Russia, many of which date back to the 1990s.
"The cooperations which we have with Russia are a result of political decisions in the 1990s after the Iron Curtain fell in order to connect Russia with the western world," Aschbacher said. "Today, we have an extremely different situation and we have to unravel what was decided then."
He added that, in addition to ExoMars and the International Space Station, ESA has contracts in place with Russia for supply of various components, which will be reviewed in the upcoming months.
The agency will reconvene with its member states in the following weeks to decide on the future steps.
"In a few months or certainly before the summer break we will have a very consolidated view on what your options are and then based on these decisions to be taken," Aschbacher said.